Real time data validation of shipping addresses?

Hi everyone

What I would like to achieve is when the user is filling in their address I want it to be compared to information within my database so that users cannot enter non-deliverable addresses.

I have all the data here in that I have a complete and comprehensive database with every street name with their respective region and postcodes for the country of interest.

So heres how I think it should work.
The user is typing in there address and the street name can auto complete as typed as with the region. The postcode is derived directly from the database and cannot be entered by the user. The same applies to the regional information, the user will not be able to enter any regional information that does not relate to the street name.

Eventually this will also tie into the shipping modules to calculate the correct shipping.

My question is:
Is this at all possible?
What files woulds I need to start looking at for this mod?

Sorry of this sounds silly, but I have no knowledge of ZC and am looking for a starting point.

Regards

Fred